The prior art filter apparatus having a bag with a resilient gasket is described in U.S. Pat. No. 4,460,468, issued July 17, 1984. Related patents include U.S. Pat. Nos.
3,771,664, issued Nov. 13, 1973, PA0 4,133,769, issued Jan. 9, 1979, PA0 4,204,966, issued May 27, 1980, PA0 4,259,188, issued Mar. 31, 1981, PA0 4,285,814, issued Aug. 25, 1981, PA0 4,419,240, issued Dec. 6, 1983, PA0 4,460,468, issued July 17, 1984, PA0 4,490,253, issued Dec. 25, 1984, and PA0 4,669,167, issued June 2, 1987.
The prior art filter apparatus having a bag with a resilient gasket includes a housing, a cover plate, and a bag filter subassembly. The bag filter subassembly has a filter bag and a rubber seal member. The seal member having a web portion and a peripheral head portion for forming a seal between the housing and the cover plate, the rubber seal being attached to the bag filter at its open end by an adhesive or heat seal.
One problem with the prior art filter apparatus is that a portion of the filter bag at its open end separates from the seal member thereby causing a leakage past the seal member.